Chapter 14 Flashcards
Active Touch
Touch in which the observer plays an active role in touching and exploring an object, usually with his or her hands.
Affective/emotional component of pain
The emotional experience associated with pain - for example, pain described as tortueing, annoying, frightful etc.
Cutaneous senses
The ability to perceive sensations such as touch and pain, that are based on the stimulation of receptors in the skin.
Dermis
Layer of skin below the epidermis
Direct Pathway model of pain
The idea that pain occurs when nociceptor receptors in the skin are stimulated and send their signals to the brain. This model does not account for the fact that pain can be affected by factors in addition to stimulation of the skin.
Duplex theory of texture perception
The idea that texture perception is is determined by both spatial and temporal cues that are detected by two types of receptors. Proposed by David Katz and named by Hollins.
Endorphin
Chemical naturally produced in the brain that causes analgesia
Epidermis
The outer layer of the skin including a layer of dead skn cells
Exploratory procedures (EPs)
Movements of hands and fingers while identifying 3D objects by touch
Gate control model
Melzack/Wall - perception of pain is controlled by a neural circuit that takes into account the relative amount of activity int he nociceptors, mechanoreceptors, and central signals. This model has been used to explain how pain can be influenced by factors in addition to stimulation of receptors in the skin.
Grating acuity
in the cutaneous senses, a measure of acuity on the skin that is the narrowest spacing of a grooved surface on the skin for which orientation can be accurately judged.
Haptic perception
The perception of 3D objects by touch
Homonculus
“little man”. Topographic map of the body in the somatosensory cortex.
Inflammatory pain
Pain caused by damage to tissues, inflammation of joints, or tumour cells. Damage releases chemicals that create an inflammatory soup that activates nociceptors.
Kinesthesis
The sense that enables us to feel the motions and positons of the limbs and body.
Mechanoreceptor
Receptor that responds to mechanical stimulation of the skin, such as pressure, stretching or vibration.
Medial Lemniscal Pathway
A pathway in the spinal chord that transmits signals from the skin toward the thalamus.
Meissner corpuscle (RA1)
Receptor in the skin associated with RA1 mechanoreceptors. It has been proposed that the Meissner corpuscle is important for perceiving tactile slip and for controlling the force needed to grip objects.
Merkel receptor (SA1)
A disk shaped receptor in the skin associated with slowly adapting fibers and the perception of fine details.
Multimodal nature of pain
The fact that the experience of pain has both sensory and emotional components.
Naloxone
A substance that inhibits the activity of opiates. It is hypothesized that naloxone also inhibits the activity of endorphins and therefore can have an effect on pain perception.
Neuropathic pain
Pain caused by lesions or other damage to the nervous system.
Nociceptive pain
This type of pain, which serves as a warning of impending damage to the skin, is caused by activation of receptors in the skin called nociceptors.
Nociceptor
A fiber that responds to stimuli that are damaging to the skin.
Opioid
A chemical such as opium, heroin, and other molecules with related structures that reduce pain and induce feelings of euphoria.
Pacinian corpuscle (RA2 or PC)
A receptor with a distinctive elliptical shape associated with RA2 mechanoreceptors. It transmits pressure to the nerve finer inside it only at the beginning or end of a pressure stimulus and is responsible for our perception of vibration and fine textures that are perceived when moving the fingers over a surface.
Pain matrix
The network of structures in the brain responsible for pain perception.
Passive touch
A situation in which a person passively receives tactile stimulation.
Phantom limb
A person’s continued perception of a limb after amputation.
Proprioception
The sensing of the position of the limbs.
Rapidly Adapting (RA) receptor
Mechanoreceptors that respond with bursts of firing just at the onset and offset of pressure stimulus. The Meissner corpuscle and the Pacinian corpuscle are rapidly adapting receptors.
Ruffini cylinder (SA2)
A receptor structure in the skin associated with slowly adapting fibers. It has been proposed that the Ruffini cylinder is involved in perceiveing “stretching”.
Secondary Somatosensory Cortex (S2)
Area in the parietal lobe next to the somatosensory receiving area that processes neural signals related to touch, temperature, and pain.
Sensory component of pain
Pain perception described with terms such as throbbing, prickly, hot, or dull.
Slowly Adapting (SA) receptor
Mechanoreceptors located in the epidermis and dermis that respond with prolonged firing to continued pressure. The Merkel receptor and the Ruffini cylinder are slowly adapting mechanoreceptors.
Somatosensory receiving area (S1)
Area in the parietal lobe that received input from the skin and viscera associated with somatic senses such as touch, temp and pain.
Somatosensory System
System that includes the cutaneous senses (senses involving the skin), proprioception (sense of positioning of the limbs) and kinaesthesia (sense of movement of the limbs).
Spatial cue
In tactile perception, information abotu the texture of a surface that is determined by the size, shape and distribution of surface elements such as bumbs and grooves.
Spinothalamic Pathway
One of the nerve pathways in the spinal cord that conducts nerve impulses from the skin to the somatosensory area of the thalamus.
Surface Texture
The visual and tactile quality of a physical surface created by peaks and valleys.
Tactile acuity
The smallest details that can be detected on the skin.
Temporal cue
Information about the texture of a surface that is determined by the rate of vibrations that occur as we move our fingers across the surface.
Transmission cell (T-cell)
According to gate control theory, the cell that receives + and = inputs from cells in the dorsal horn. T-cell activity determines perception of pain.
Two-point threshold
smallest separation between two points on the skin that is perceived as two points.
Ventrolateral nucleus
Nucleus in the thalamus that receives signals from the cutaneous system.
